Actual Conductivity: Value measured using a properly
calibration Conductivity/TDS/Temperature meter.
Both the actual TDS and the actual conductivity values
must be in the same magnitude of units. For example, if
the TDS value in is ppm, the conductivity value must be
in µS; if the TDS value is in ppt, the conductivity value
must be in mS.
Check this number by multiplying the conductivity
reading by the factor in the above formula and the
result is the TDS in ppm.
Appendix C: Temperature Effect
Conductivity measurements are temperature dependent,
if the temperature increases, conductivity increases.
For example the conductivity measured in a 0.01M KCl
solution at 20°C is 1.273 mS/cm whereas, at 25°C, it is
1.409 mS/cm.
The concept of reference temperature (Normalization
temperature) was introduced to allow the comparison of
conductivity results obtained at different temperature.
The reference temperature is usually 20°C or 25°C. The
conductivity meter measures the actual conductivity
and temperature and then converts it to the reference
temperature using a temperature correction function
and displays the conductivity at the reference
temperature.
It is mandatory to always associate the temperature
together with a conductivity result. If no temperature
correction is applied, the conductivity is the value taken
at measurement temperature.
The WT-20 use linear temperature correction.
Linear temperature correction:
In moderately and highly conductive solutions,
temperature correction can be based on a linear
equation involving a temperature coefficient (
q
). The
coefficient is usually expressed as a conductivity variation
in % / °C.
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